JIA is a disease in which a cure is not available. This research demonstrates a beneficial effect from both combined hydrotherapy and land-based physiotherapy treatment and land-based physiotherapy treatment alone in JIA without any exacerbation of disease, indicating that treatments are safe. The caveat to the results of the cost-effectiveness and clinical efficacy analysis is that the restricted sample size could have prevented a true difference being detected between the groups. Nevertheless, there appears to be no evidence to justify the costs of building pools or initiating new services specifically for use in this disease. However, this conclusion may not apply to patients with unremitting active disease who could not be entered into the trial because of specified exclusion criteria. For this group, hydrotherapy or combined treatment may still be the only physiotherapy option. Further research is suggested into: the investigation and development of appropriate and sensitive outcome measures for use in future hydrotherapy and physiotherapy trials of JIA; preliminary studies of methodologies in complex interventions such as physiotherapy and hydrotherapy to improve recruitment and ensure protocol is acceptable to patients and carers; hydrotherapy in the most common paediatric user group, children with neurological dysfunction, ensuring appropriate outcome measures are available and methodologies previously tried; patient satisfaction and compliance in land-based physiotherapy and hydrotherapy and European studies of hydrotherapy in rare disorders such as JIA.